Method and apparatus for sharing big data using block chain

ABSTRACT

Provided are a device and method for sharing big data using a blockchain. The method of sharing big data using a blockchain includes receiving a search condition from a user terminal, searching a blockchain network for metadata meeting the received search condition and acquiring found metadata, acquiring shared data stored in a distributed storage using the acquired metadata, and transmitting the acquired shared data to the user terminal.

CLAIM FOR PRIORITY

This application claims priority to Korean Patent Application No.2019-0012054 filed on Jan. 30, 2019 in the Korean Intellectual PropertyOffice (KIPO), the entire contents of which are hereby incorporated byreference.

BACKGROUND 1. Technical Field

Example embodiments of the present invention relate in general to adevice and method for sharing big data using a blockchain and morespecifically to a technology for facilitating sharing and use of bigdata by managing and distributing big data collected from multiple datasharers on the basis of a block chain and a distributed storage.

2. Related Art

With the proliferation of data communication technology, numerous piecesof data generated by various subjects are shared and consumed in realtime, and accordingly, big data technologies are attracting attention. Abig data technology is to extract values from a large number of datasets beyond an existing database management level and analyze extractionresults.

In general, common characteristics of big data include the amount ofdata, data generation velocity, and the variety of forms. Recently, newcharacteristics include veracity which represents whether collected datais accurate, variability which represents that data has differentmeanings according to a subject or method of analyzing the data andmaking a decision, and visualization, whereby data is processed to beunderstandable by users.

As a big data processing technique for analyzing and using big datahaving such a variety of characteristics, various methods including thedistributed data processing technology of MapReduce and the like areunder discussion. However, for distributed data processing, existingmethods require a single service provider to have an expensivedistributed storage system or a security system for preventing anexternal attack.

Meanwhile, the blockchain technology for containing data in blocks,connecting the blocks in a chain form, and simultaneously copying andstoring the chain in numerous computers is attracting attentionrecently. However, the blockchain technology involves a process ofcalculating and verifying a hash value and the like in order to maintainthe integrity of data. Therefore, the blockchain technology is notappropriate for storing a large amount of data.

SUMMARY

Accordingly, example embodiments of the present invention are providedto substantially obviate one or more problems due to limitations anddisadvantages of the related art.

Example embodiments of the present invention provide a method of sharingbig data using a blockchain.

Example embodiments of the present invention also provide a device forsharing big data using a blockchain.

In some example embodiments, a method of sharing big data using ablockchain is provided.

In other example embodiments, a device for sharing big data using ablockchain is provided.

BRIEF DESCRIPTION OF DRAWINGS

Example embodiments of the present invention will become more apparentby describing in detail example embodiments of the present inventionwith reference to the accompanying drawings, in which:

FIG. 1 is a conceptual diagram illustrating operation of a device andmethod for sharing big data using a blockchain according to an exampleembodiment of the present invention.

FIG. 2 is a diagram showing a configuration of a blockchain according toan example embodiment of the present invention.

FIG. 3 is a block diagram of a distributed storage according to anexample embodiment of the present invention.

FIG. 4 is an example diagram illustrating a data sharing method in adevice and method for sharing big data using a blockchain according toan example embodiment of the present invention.

FIG. 5 is an example diagram illustrating a data acquisition method in adevice and method for sharing big data using a blockchain according toan example embodiment of the present invention.

FIG. 6 is a flowchart of a method of sharing big data using a blockchainaccording to an example embodiment of the present invention.

FIG. 7 is a block diagram showing a configuration of a device forsharing big data using a blockchain according to an example embodimentof the present invention.

FIG. 8 is an example diagram illustrating effects of a device and methodfor sharing big data using a blockchain according to an exampleembodiment of the present invention.

DESCRIPTION OF EXAMPLE EMBODIMENTS

Example embodiments of the present invention are disclosed herein.However, specific structural and functional details disclosed herein aremerely representative for purposes of describing example embodiments ofthe present invention, however, example embodiments of the presentinvention may be embodied in many alternate forms and should not beconstrued as limited to example embodiments of the present invention setforth herein.

Accordingly, while the invention is susceptible to various modificationsand alternative forms, specific embodiments thereof are shown by way ofexample in the drawings and will herein be described in detail. Itshould be understood, however, that there is no intent to limit theinvention to the particular forms disclosed, but on the contrary, theinvention is to cover all modifications, equivalents, and alternativesfalling within the spirit and scope of the invention. Like numbers referto like elements throughout the description of the figures.

It will be understood that, although the terms first, second, etc. maybe used herein to describe various elements, these elements should notbe limited by these terms. These terms are only used to distinguish oneelement from another. For example, a first element could be termed asecond element, and, similarly, a second element could be termed a firstelement, without departing from the scope of the present invention. Asused herein, the term “and/or” includes any and all combinations of oneor more of the associated listed items.

It will be understood that when an element is referred to as being“connected” or “coupled” to another element, it can be directlyconnected or coupled to the other element or intervening elements may bepresent. In contrast, when an element is referred to as being “directlyconnected” or “directly coupled” to another element, there are nointervening elements present. Other words used to describe therelationship between elements should be interpreted in a like fashion(i.e., “between” versus “directly between”, “adjacent” versus “directlyadjacent”, etc.).

The terminology used herein is for the purpose of describing particularembodiments only and is not intended to be limiting of the invention. Asused herein, the singular forms “a”, “an” and “the” are intended toinclude the plural forms as well, unless the context clearly indicatesotherwise. It will be further understood that the terms “comprises”,“comprising,”, “includes” and/or “including”, when used herein, specifythe presence of stated features, integers, steps, operations, elements,and/or components, but do not preclude the presence or addition of oneor more other features, integers, steps, operations, elements,components, and/or groups thereof.

Unless otherwise defined, all terms (including technical and scientificterms) used herein have the same meaning as commonly understood by oneof ordinary skill in the art to which this invention belongs. It will befurther understood that terms, such as those defined in commonly useddictionaries, should be interpreted as having a meaning that isconsistent with their meaning in the context of the relevant art andwill not be interpreted in an idealized or overly formal sense unlessexpressly so defined herein.

It should also be noted that in some alternative implementations, thefunctions/acts noted in the blocks may occur out of the order noted inthe flowcharts. For example, two blocks shown in succession may in factbe executed substantially concurrently or the blocks may sometimes beexecuted in the reverse order, depending upon the functionality/actsinvolved.

FIG. 1 is a conceptual diagram illustrating operation of a device andmethod for sharing big data using a blockchain according to an exampleembodiment of the present invention.

Referring to FIG. 1, elements for a method of sharing big data using ablockchain may include a big data sharing device 10 which provides a bigdata sharing service according to a search request, a user terminal 50which is provided with a search service, a blockchain network 20 whichstores and manages metadata of search result data in blocks, adistributed storage 30 which stores the search result data correspondingto the metadata in a distributed manner, and/or a data owner terminal 40which generates various kinds of data and provides the generated data toother users for sharing.

The data owner terminal 40 is a terminal which provides its own data forbig data sharing. The data owner terminal 40 may also serve as a nodeconstituting the blockchain network 20 and may further serve as anindividual node constituting the distributed storage 30.

The blockchain network 20 is composed of a plurality of nodes connectedin a wired or wireless manner. The plurality of nodes may generatemetadata of the various kinds of data which has been provided by thedata owner terminal 40 for sharing, generate blocks using the generatedmetadata, and generate a blockchain by connecting the generated blockstogether. The generated blockchain is equally distributed to individualnodes constituting the blockchain network 20 and stored therein suchthat the integrity of data may be ensured.

Meanwhile, the various kinds of data provided by the data owner terminal40 may be stored in the separate distributed storage 30. The distributedstorage 30 is a storage for storing actual data, which is accessiblethrough the metadata stored in the blockchain network 20, in adistributed manner. Individual nodes constituting the distributedstorage 30 may also serve as nodes of the blockchain network 20 and mayfurther serve as the data owner terminal 40.

The big data sharing device 10 is an agent which provides a big datasharing service to the user terminal 50 using the blockchain network 20and the distributed storage 30 and may be implemented as a server. Thebig data sharing device 10 may also serve as at least one of a code ofthe blockchain network 20, a node constituting the distributed storage30, and the data sharing terminal 40.

A representative example in which the method of sharing big data using ablockchain according to an example embodiment of the present inventionis performed may be a search service based on big data sharing.Specifically, referring to FIG. 1, the user terminal 50 may access thebig data sharing device 10 and input a search condition. The big datasharing device 10 may search for metadata of the search conditionthrough the blockchain network 20. The blockchain network 20 may providefound metadata to the big data sharing device 10. Examples of metadatamay be a hash value of data to be actually used as big data, an identity(ID) of an owner, and the like.

When the metadata is acquired through the blockchain network 20, the bigdata sharing device 10 may search the distributed storage 30 for datacorresponding to the acquired metadata and acquire search result dataaccording to the metadata from the distributed storage 30. The big datasharing device 10 may provide the search result data, which is acquiredfrom the distributed storage 30, to the user terminal 50.

Meanwhile, when the search result data acquired by the big data sharingdevice 10 from the distributed storage 30 has been encrypted or it isdetermined that the metadata acquired through the blockchain network 20does not contain the owner's permission for sharing, the big datasharing device 10 may check the data owner terminal 40 using ownerinformation included in the metadata, query the checked data ownerterminal 40 whether to permit sharing with the user terminal 50, andacquire whether to permit sharing from the data owner terminal 40. Amessage for querying whether to permit sharing may include an ID of theuser terminal 50. In this case, the big data sharing device 10 mayprovide the search result data to the user terminal 50 as long as apermission for sharing is acquired from the data owner terminal 40.

Examples of individual nodes constituting the blockchain network 20 orthe distributed storage 30, the big data sharing device 10, the dataowner terminal 40, or the user terminal 50 may be a desktop computer, alaptop computer, a smart phone, a tablet personal computer (PC), amobile phone, a smart watch, smart glasses, an e-book reader, a portablemultimedia player (PMP), a portable game machine, a navigation device, adigital camera, a digital multimedia broadcasting (DMB) player, adigital audio recorder, a digital audio player, a digital videorecorder, a digital video player, a personal digital assistant (PDA),etc. capable of communication.

FIG. 2 is a diagram showing a configuration of a blockchain according toan example embodiment of the present invention.

Referring to FIG. 2, it is possible to view a configuration of ablockchain 21 which is copied and stored in individual nodesconstituting the blockchain network 20 of FIG. 1.

Specifically, the blockchain 21 may include a coin ledger 21 a, a dataprivilege ledger 21 b, and metadata 21 c.

The coin ledger 21 a may be a ledger storing transaction details ofcoins which are provided as compensation for data sharing of individualnodes constituting the blockchain network 20.

The data privilege ledger 21 b is a ledger storing data ownership and aright of using data indicated by the metadata 21 c. The data ownershipmay belong to an initial data generator and may be represented by aunique ID of the initial data generator. Also, the right of using datamay not only include transfer of the right of using the data indicatedby the metadata 21 c and the period of use of the data but also includewhether an owner has permitted data sharing (including permitted personswhen only some specific persons are permitted). The metadata 21 c isdescriptive information used to efficiently retrieve or access dataprovided by various data owner terminals including an Internet of things(IoT) device, a connected car, etc. and may include path (or link)information with which it is possible to access the data provided by thedata owner terminals.

Specifically, the metadata 21 c may include generation times (Timestamp)21 d, categories (Category) 21 e, owners (Owner or Creator) 21 f, datasizes (Size) 21 g, related search words or keywords (Keyword) 21 h, etc.of the data provided by the data owner terminals. Also, the metadata 21c may include access paths or hash values (DataHash) 21 i with which itis possible to access the data provided by the data owner terminals. Thehash values 21 i may be values obtained by encrypting path (or link)information, with which it is possible to access actual data, with ahash function. A Message Digest algorithm 5 (MD5) or Secure HashAlgorithm (SHA) function may be used as the hash function.

FIG. 3 is a block diagram of a distributed storage according to anexample embodiment of the present invention.

Referring to FIG. 3, it is possible to view a configuration of thedistributed storage 30 of FIG. 1. Specifically, in the distributedstorage 30 according to an example embodiment of the present invention,at least one of a distributed peer storage 30 a and a centralizedstorage 30 b may be used.

The distributed peer storage 30 a is a peer-to-peer (P2P) distributedfile system and may be a storage in which stored data is accessiblethrough a hash value. Since the distributed peer storage 30 a implementsdata storage by cloud sourcing, it is possible to reduce systemmaintenance cost. Also, as long as enough nodes are provided toconstitute the distributed peer storage 30 a, the storage capacity maybe continuously increased. Further, it is possible to prevent data lossand tampering by redundantly storing stored data in other nodes. Anexample of the distributed peer storage 30 a may be the InterPlanetaryFile System (IPFS). The distributed peer storage 30 a may generate ahash value of a file to be uploaded and provide the hash value to a fileowner, and the file owner may access the corresponding file using thehash value.

The centralized storage 30 b is a distributed storage system whichstores data in a distributed manner through a centralized server farm.The centralized storage 30 b may be mainly used to control data,minimize the risk of data leakage, and store data sensitive to leakagethrough the centralized server farm. An example of the centralizedstorage 30 b may be the Hadoop Distributed File System (HDFS). Thecentralized storage 30 b may divide a file to be stored into blocks andstore the file divided into blocks in distributed servers. In this case,the servers which store the file divided into blocks may be referred toas data nodes, and a server which manages metadata of files stored inthe data nodes and inputs or outputs the files may be referred to as aname node. In other words, the centralized storage 30 b may performcentralized file access through the name node.

As a distributed storage according to an example embodiment of thepresent invention, the above-described distributed peer storage 30 a andcentralized storage 30 b may be used together or selectively accordingto the type, attribute, etc. of data to be shared. For example, dataneeding to be shared among some specific groups only may be stored inthe centralized storage 30 b, and data needing to be widely shared amonga large number of external users may be stored in the distributed peerstorage 30 a.

FIG. 4 is an example diagram illustrating a data sharing method in adevice and method for sharing big data using a blockchain according toan example embodiment of the present invention.

Referring to FIG. 4, the data owner terminal 40 may store data to bestored in the distributed peer storage 30 a or the centralized storage30 b. At this time, the distributed peer storage 30 a may generate ahash value for accessing the stored data and transmit the hash value tothe data owner terminal 40. Also, the centralized storage 30 b maygenerate an access path to the stored data and transmit the access pathto the data owner terminal 40. More specifically, the name node of thecentralized storage 30 b may divide the data received from the dataowner terminal 40 into blocks and store the respective blocks in a largenumber of data nodes in a distributed manner, and the data nodes maytransmit block IDs, lengths, generation times, etc. of the blocks storedtherein to the name node. The name node may manage the block IDs,lengths, generation times, etc. received from the data nodes togetherwith IDs of the data nodes.

After storing the data in the distributed peer storage 30 a or thecentralized storage 30 b, the data owner terminal 40 may request sharingof data including a hash value, an access path, etc. from the blockchainnetwork 20. The individual nodes constituting the blockchain network 20may generate metadata of a file requested for data sharing, generate ablock with the generated metadata, and then connect the generated blockto the blockchain.

Meanwhile, it has been described above that the data owner terminal 40requests storage and sharing of data firsthand. However, when the dataowner terminal 40 transmits a message for requesting sharing togetherwith data to be shared to the big data sharing device 10 of FIG. 1, thebig data sharing device 10 may store the data in the distributed storage30 a or 30 b and request data sharing from the blockchain network 20.

FIG. 5 is an example diagram illustrating a data acquisition method in adevice and method for sharing big data using a blockchain according toan example embodiment of the present invention.

Referring to FIG. 5, the big data sharing device 10 may search theblockchain network 20 for metadata of necessary data and acquire anaccess path or a hash value of data indicated by metadata which isidentical or similar to the searched metadata.

The big data sharing device 10 may acquire the data by accessing thecentralized storage 30 b through the acquired access path or acquire thedata by transferring the acquired hash value to the distributed peerstorage 30 a.

FIG. 6 is a flowchart of a method of sharing big data using a blockchainaccording to an example embodiment of the present invention.

Referring to FIG. 6, the method of sharing big data using a blockchainmay include an operation of receiving a search condition from a userterminal, an operation of searching a blockchain network for metadatameeting the received search condition and acquiring found metadata, anoperation of acquiring shared data stored in a distributed storage usingthe acquired metadata, and an operation of transmitting the acquiredshared data to the user terminal.

The method of sharing big data using a blockchain may be performed bythe big data sharing device 10 of FIG. 1.

A blockchain stored in a plurality of nodes constituting the blockchainnetwork may include the metadata and a data privilege ledger in whichownership of the data indicated by the metadata and the data usage rightare defined.

The metadata may include at least one of a generation time Timestamp, acategory Category, an owner or creator Owner (Creator), a data sizeSize, a related search word or index word Keyword, an access path, and ahash value DataHash of the data indicated by the metadata.

The distributed storage may include at least one of a distributed peerstorage and a centralized storage.

After the operation of acquiring the metadata, the method may furtherinclude an operation of checking the right of using the data withreference to the data privilege ledger, an operation of acquiring anowner ID indicated by the ownership when the user terminal does not havethe right of using the data, and an operation of querying a data ownerterminal corresponding to the acquired owner ID whether to permitsharing of the data.

After the operation of acquiring the shared data, the method may furtherinclude an operation of determining whether the shared data has beenencrypted, an operation of acquiring the owner ID indicated by theownership when the shared data has been encrypted, and an operation ofquerying the data owner terminal corresponding to the acquired owner IDabout a decryption key.

The operation of acquiring the shared data may include an operation oftransmitting the hash value to the distributed peer storage andacquiring the shared data corresponding to the hash value.

The operation of acquiring the shared data may include an operation ofacquiring the shared data by accessing the centralized storage throughthe access path.

FIG. 7 is a block diagram showing a configuration of a device forsharing big data using a blockchain according to an example embodimentof the present invention.

Referring to FIG. 7, a device 100 for sharing big data using ablockchain may include at least one processor 110 and a memory 120storing instructions for instructing the at least one processor 110 toperform at least one operation.

The at least one processor 110 may be a central processing unit (CPU), agraphics processing unit (GPU), or a dedicated processor whereby methodsaccording to example embodiments of the present invention are performed.Each of the memory 120 and a storage device 160 may be at least one of avolatile storage medium and a non-volatile storage medium. For example,the memory 120 may be at least one of a read-only memory (ROM) and arandom access memory (RAM).

Also, the device 100 for sharing big data using a blockchain may includea transceiver 130 which performs communication via a wireless network.The device 100 for sharing big data using a blockchain may furtherinclude an input interface device 140, an output interface device 150,the storage device 160, and the like. The respective elements includedin the device 100 for sharing big data using a blockchain may beconnected through a bus 170 and communicate with each other.

The at least one operation may include an operation of receiving asearch condition from a user terminal, an operation of searching ablockchain network for metadata meeting the received search conditionand acquiring found metadata, an operation of acquiring shared datastored in a distributed storage using the acquired metadata, and anoperation of transmitting the acquired shared data to the user terminal.

The device 100 for sharing big data using a blockchain may be a devicewhich is identical to or corresponds to the big data sharing device 10of FIG. 1.

A blockchain stored in a plurality of nodes constituting the blockchainnetwork may include the metadata and a data privilege ledger in whichownership of the data indicated by the metadata and the right of usingthe data are defined.

The metadata may include at least one of a generation time Timestamp, acategory Category, an owner or creator Owner (Creator), a data sizeSize, a related search word or index word Keyword, an access path, and ahash value DataHash of the data indicated by the metadata.

The distributed storage may include at least one of a distributed peerstorage and a centralized storage.

After the operation of acquiring the metadata, the at least oneoperation may further include an operation of checking the right ofusing the data with reference to the data privilege ledger, an operationof acquiring an owner ID indicated by the ownership when the userterminal does not have the right of using the data, and an operation ofquerying a data owner terminal corresponding to the acquired owner IDwhether to permit sharing of the data.

After the operation of acquiring the shared data, the at least oneoperation may further include an operation of determining whether theshared data has been encrypted, an operation of acquiring the owner IDindicated by the ownership when the shared data has been encrypted, andan operation of querying the data owner terminal corresponding to theacquired owner ID about a decryption key.

The operation of acquiring the shared data may include an operation oftransmitting the hash value to the distributed peer storage andacquiring the shared data corresponding to the hash value.

The operation of acquiring the shared data may include an operation ofacquiring the shared data by accessing the centralized storage throughthe access path.

FIG. 8 is an example diagram illustrating effects of a device and methodfor sharing big data using a blockchain according to an exampleembodiment of the present invention.

There are various kinds of data which form big data, and variouscompanies want to provide such data. When such pieces of data areseparately provided, it is difficult to integrate the pieces of datawith each other. Therefore, it is difficult to enhance the service,maintain data, manage data, and reduce costs.

However, when the device and method for sharing big data using ablockchain according to an example embodiment of the present inventionare used, it is possible to easily and conveniently share new types ofdata by storing only metadata of shared data in a blockchain and storingshared data which will be actually shared in a distributed storage.

For example, when a plurality of service providers separately provideindividual data sharing services as shown in FIG. 8, all of theplurality of service providers may acquire and provide data using ablockchain network according to an example embodiment of the presentinvention. In this case, integration of data makes it possible toprovide data sharing services which are far more useful.

In particular, it is possible to easily add a new service by only addinga new node to a blockchain network according to an example embodiment ofthe present invention such that new services may be vigorously created.

Also, since only metadata is stored using a blockchain and an accesspath to data to be shared is provided through only metadata, the risk ofdata leakage is low, and high security is provided.

When the device and method for sharing big data using a blockchainaccording to an example embodiment of the present invention are used, itis possible to easily and conveniently share new types of data.

Also, since a blockchain and a distributed storage are managed together,the risk of data leakage is low, and high security is providedaccordingly.

While the example embodiments of the present invention and theiradvantages have been described in detail, it should be understood thatvarious changes, substitutions and alterations may be made hereinwithout departing from the scope of the invention.

What is claimed is:
 1. A method of sharing big data using a blockchain,the method being performed by a big data sharing device and comprising:receiving a search condition from a user terminal; searching ablockchain network for metadata meeting the received search conditionand acquiring found metadata; acquiring shared data stored in adistributed storage using the acquired metadata; and transmitting theacquired shared data to the user terminal.
 2. The method of claim 1,wherein a blockchain stored in a plurality of nodes constituting theblockchain network includes: the metadata; and a data privilege ledgerin which ownership of the data indicated by the metadata and a right ofusing the data are defined.
 3. The method of claim 1, wherein themetadata includes at least one of a generation time, a category, anowner or creator, a data size, a related search word or keyword, anaccess path, and a hash value of the data indicated by the metadata. 4.The method of claim 3, wherein the distributed storage includes at leastone of a distributed peer storage and a centralized storage.
 5. Themethod of claim 2, further comprising, after the acquiring of themetadata: checking the right of using the data with reference to thedata privilege ledger; acquiring an owner identity (ID) indicated by theownership when the user terminal does not have the right of using thedata; and querying a data owner terminal corresponding to the acquiredowner ID whether to permit sharing of the data.
 6. The method of claim2, further comprising, after the acquiring of the shared data:determining whether the shared data has been encrypted; acquiring anowner identity (ID) indicated by the ownership when the shared data hasbeen encrypted; and querying a data owner terminal corresponding to theacquired owner ID about a decryption key.
 7. The method of claim 4,wherein the acquiring of the shared data comprises transmitting the hashvalue to the distributed peer storage and acquiring the shared datacorresponding to the hash value.
 8. The method of claim 4, wherein theacquiring of the shared data comprises acquiring the shared data byaccessing the centralized storage through the access path.
 9. A devicefor sharing big data using a blockchain, the device comprising: at leastone processor; and a memory configured to store instructions forinstructing the at least one processor to perform at least oneoperation, wherein the at least one operation comprises: receiving asearch condition from a user terminal; searching a blockchain networkfor metadata meeting the received search condition and acquiring foundmetadata; acquiring shared data stored in a distributed storage usingthe acquired metadata; and transmitting the acquired shared data to theuser terminal.
 10. The device of claim 9, wherein a blockchain stored ina plurality of nodes constituting the blockchain network includes: themetadata; and a data privilege ledger in which ownership of the dataindicated by the metadata and a right of using the data are defined. 11.The device of claim 9, wherein the metadata includes at least one of ageneration time, a category, an owner or creator, a data size, a relatedsearch word or keyword, an access path, and a hash value of the dataindicated by the metadata.
 12. The device of claim 11, wherein thedistributed storage includes at least one of a distributed peer storageand a centralized storage.
 13. The device of claim 10, wherein the atleast one operation further comprises, after the acquiring of themetadata: checking the right of using the data with reference to thedata privilege ledger; acquiring an owner identity (ID) indicated by theownership when the user terminal does not have the right of using thedata; and querying a data owner terminal corresponding to the acquiredowner ID whether to permit sharing of the data.
 14. The device of claim10, wherein the at least one operation further comprises, after theacquiring of the shared data: determining whether the shared data hasbeen encrypted; acquiring an owner identity (ID) indicated by theownership when the shared data has been encrypted; and querying a dataowner terminal corresponding to the acquired owner ID about a decryptionkey.
 15. The device of claim 12, wherein the acquiring of the shareddata comprises transmitting the hash value to the distributed peerstorage and acquiring the shared data corresponding to the hash value.16. The device of claim 12, wherein the acquiring of the shared datacomprises acquiring the shared data by accessing the centralized storagethrough the access path.